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"Struktur Olivine LiMnPO4 sebagai material katoda baterai Li-ion memiliki daya tarik tersendiri dikarenakan nilai potensial oksidasi-reduksi yang tinggi yaitu 4.2 volt terhadap Li/Li+, stabil secara termal, dan relatif ramah lingkungan (nontoxic).Namun nilai konduktifitas ionik dan elektronik yang rendah sekitar (10-9 S/cm), nilai specific capacity yang rendah akibat distorsi kisi (Jahn-Teller effect),menjadi tantangan tersendiri. Proses pelapisan karbon pada bahan aktif LiMnPO4 dengan menggunakan starch atau pati singkong , subtitusi kation dengan penambahan Fe dan Ni (covalent-doping) dimana formulasi LiMn0.7Fe0.3-xNixPO4/C dengan 0 X 0.2 digunakan untuk meningkatkan konduktifitas elektronik-ionik, nilai specific capacity dan working voltage (Voksidasi/reduksi).Pengujian XRD menunjukan pola difraksi struktur kristal LiMnPO4 telah berhasil terbentuk melalui proses milling (330 rpm, 48 jam) dan sintering disuhu 800°C (solid state reaction). Proses reduksi ukuran dan coating karbon dengan Ball Milling mampu menghasilkan partikel bahan aktif LiMn0.7Fe0.3-xNixPO4/C dengan 0 X 0.2 berukuran hingga 290 nanometer dengan ukuran kristalit hingga 60 nanometer. Pertumbuhan pelapisan karbon kearah horizontal pada bahan aktif LiMn0.7Fe0.3-xNixPO4/C dengan 0 X 0.2 menjadi bukti bahwa starch atau pati singkong berperan sebagai fasilitator pengintian pelapisan karbon dan terlihat pada pengujian SEM (perbesaran 50000 x) dan pengujian EDX dengan kadar Mnyang tinggi menjadi bukti penguat. Frame network polianion terbentuk pada bahan aktif LiMn0.7Fe0.3-xNixPO4/C dengan 0 X 0.2 ditandai dengan nilai vibrasi v1- v4 (1138 dan 1098 cm-1) yang dominan muncul pada hasil pengujian FTIR. Penambahan karbon sebagai pelapis bahan aktif memberikan nilai konduktifitas elektronik (pasif) dan ionik (aktif) yang cukup tinggi sekitar 1 x 10-3 S/cm dan 7.2 S/cm, dimana penambahan Ni (doping kation) berkontribusi dalam peningkatan nilai konduktifitas elektronik (pasif). Komposisi bahan aktifLiMn0.7Fe0.25Ni0.05PO4/C menunjukan nilai specific capacity oksidasi hingga 60.92 mAh/gr dan nilai Voksidasi-reduksi sekitar 4.13 volt dan mampu digunakansebagai bahan aktif katoda baterai Li-ion secara praktikal dari hasil pengujian cyclic voltammetry. Puncak Voksidasi/reduksi ganda yang merupakan kontribusiVoksidasi Fe2+/Fe3+ dan Mn2+/Mn3+ sering terlihat pada hasil pengujian cyclic voltammetry.......Olivine LiMnPO4 structure as cathode material in Li-ion battery have veryattractive because its high potential oxidation/reduction around 4.2 volts vs. Li/Li+,thermally stable, and nontoxic. Its low electronic and ionic conductivity around(10-9 S/cm), low specific capacity by lattice distortion (Jahn-Teller effect),become its challenges. Carbon-coating process with starch of cassava in cathodematerial LiMnPO4, co-subtitution by adding Fe and Ni where LiMn0.7Fe0.3-xNixPO4/C with 0
X
0.2 formulation have been used to enhanced ionicelectronicconductivity, specific capacity, and working voltage of cathode material.Pattern diffraction of XRD shown LiMnPO4 structure have been formed viamilling process (330 rpm, 48 hours) and sintering process at 800°C (solid statereaction). Size reduction process and carbon coating have been carried andproduced cathode material LiMn0.7Fe0.3-xNixPO4/C with 0
X
0.2 with theparticle size up to 290 nanometers and crystallite size up to 60 nanometers.Carbon-coating process have been grown in horizontal direction in cathodematerial LiMn0.7Fe0.3-xNixPO4/C with 0
X
0.2 and become approval that thestarch of cassava have been facilitates nuklea of carbon-coating to grown incathode material and can be seen by SEM with magnification 50000 times, andalso the high content of Mn that have founded by EDX evaluation agreed. Framenetwork of polyanion have formed in cathode material LiMn0.7Fe0.3-xNixPO4/C with 0
X
0.2 indicated by vibration value of v1- v4 (1138 and 1098cm-1) that appeared dominantly during FTIR evaluation. Electronic conductivity(passive) of cathode material LiMn0.7Fe0.3-xNixPO4/C with 0
X
0.2 increasedsignificantly up to 1 x 10-3 S/cm by carbon-adding process as carbon-coating incathode material, where the process of Ni-added as cation-doping also contributein increasing the value of electronic conductivity. Based of cyclic voltammetryevaluation the formulation LiMn0.7Fe0.25Ni0.05PO4/C of cathode material shownthe highest specific capacity oxidation near 60.92 mAh/gr and Voxidation/reductionaround 4.13 volts and practically can be used as Li-ion battery. DobletVoxidation/reduction peak appeared several times as the contribution of Voxidation/reductionFe2+/Fe3+ and Mn2+/Mn3+ in cyclic voltammetry evaluation."

"Poli Vinil Klorida (PVC) memiliki nilai kegunaan yang luas dan beragam dikarenakan sifat mekaniknya yang dapat disesuaikan dengan kebutuhan (contoh : Unplasticized PVC dan Plasticized PVC dimana penggunaan plasticized PVC mencapai 60% dari konsumsi PVC diseluruh dunia), namun memiliki keterbatasan dalam sifat kestabilan termal selama proses pencampuran hot melt mixing P-PVC. Kebutuhan akan plasticized-poly (vinyl chloride) (P-PVC) dengan nilai modulus kekakuan (modulus young) yang optimum dan nilai kekuatan tarik (tensile strength) yang tinggi dapat dicapai dengan menerapkan formulasi aditif plasticizer dan filler CaCO3 serta pengaturan nilai parameter proses hot melt mixing seperti suhu, waktu dan kecepatan pencampuran dalam ranah nilai yang optimal, dan penggunaan heat stabilizer beserta co-heat stabilizer epoxidized soya bean oil (ESBO) ditujukan untuk mengatasi keterbatasan termal P-PVC selama proses pencampuran P-PVC dalam alat rheomix (twin screw extruder). Studi ini berusaha untuk memformulasikan filler CaCO3, plasticizer di-octyl Phatalate (DOP) dan ESBO serta parameter proses pencampuran dalam proses pencampuran PVC-P, dengan memvariasikan kadar filler CaCO3 dari 0 hingga 90 PHR (part per hundred PVC resin) dan ESBO di nilai 0 hingga 6 PHR dengan menjaga kadar DOP tetap di nilai 28 PHR dalam resin PVC-XXX selama proses pencampuran lelehan, serta memvariasikan suhu pencampuran di suhu 170˚C hingga 200˚C, variasi waktu mixing dari 60 hingga 420 sekon dan memvariasikan kecepatan mixing di angka 90 hingga 120 rpm untuk mencapai nilai modulus kekakuan dan nilai kekuatan tarik yang optimal. Hasil menunjukan bahwa penambahan filler CaCO3 dari 0 hingga 90 PHR dalam proses pencampuran lelehan mampu meningkatkan nilai kekakuan PVC-P. Nilai kekuatan tarik dan modulus kekakuan mencapai nilai optimum di suhu, waktu dan kecepatan pencampuran di nilai 180˚C, 300s dan 100 rpm. Hal yang menarik adalah bahwa ESBO tidak hanya bertindak sebagai co-heat stabilizer, disaat bersamaan penambahan ESBO dari 0 hingga 4 PHR mampu menurunkan nilai modulus kekakuan (bertindak seperti plasticizer) PVC-P, dan ini menunjukkan bahwa ESBO berpotensi untuk digunakan sebagai primary plasticizer yang berarti mengurangi penggunaan DOP. ......Poly (vinyl chloride) has versatile and varies application due to its mechanical properties that can be adjusted correspond to consumer needs (ex. Unplasticized PVC and Plasticized PVC where the usage of plasticized PVC reach 60% from all PVC consumption around the world), but still have many limitations which is PVC is unstable during processing (hot melt mixing). Demand of plasticized PVC with high tensile strength and modulus young can be achieved by optimizing the formulation of plasticizer, filler CaCO3 with other additive and apply the optimum adjustment of mixing parameter process (temperature, time, and speed of mixing), and the usage of heat stabilizer and co-heat stabilizer epoxidized soya bean oil (ESBO) where synergize to stabilizing the molecules of plasticized PVC during processing. The aim of this research is to formulate the additive (filler, DOP, ESBO) and mixing parameter process which is can produce plasticized PVC with high mechanical properties by varying the concentration of filler CaCO3 from 0 up to 90 PHR (parts per hundred PVC resin) and the concentration of ESBO from 0 up to 6 PHR while at the same time keeping the concentration of DOP still on 28 PHR in matrix of PVC-P during hot melt mixing, and varying the mixing temperature from 170˚C going to 200˚, varying the duration of mixing from 60 going to 420 seconds and varying the speed of mixing from 90 going to 120 rpm to obtain the optimum of modulus young and tensile strength properties. The result shown that the optimum modulus young and tensile strength of plasticized PVC was achieved by setting temperature, time, and rpm of hot melt mixing in certain value respectively 180˚C, 300 seconds and 100 rpm. The remarks is that ESBO is not only acted as co-heat stabilizer, at the same time the addition of ESBO from 0 up to 4 PHR can reduce the modulus young properties of plasticized PVC (ESBO acted as secondary plasticizer), and this lead to conclusion that ESBO has a great potential to become primary plasticizer to reduce the usage of DOP that can be reduce the risk in health issue during processing of plasticized PVC."